Aplastic anemia is a condition that occurs when your body stops producing enough new blood cells. Aplastic anemia leaves you feeling fatigued and with a higher risk of infections and uncontrolled bleeding.

A rare and serious condition, aplastic anemia can develop at any age. Aplastic anemia may occur suddenly, or it can occur slowly and get worse over a long period of time. Treatment for aplastic anemia may include medications, blood transfusions or a stem cell transplant.

Aplastic anemia symptoms may include:

Fatigue

Shortness of breath with exertion

Rapid or irregular heart rate

Pale skin

Frequent or prolonged infections

Unexplained or easy bruising

Nosebleeds and bleeding gums

Prolonged bleeding from cuts

Skin rash

Dizziness

Headache

Aplastic anemia can progress slowly over weeks or months, or it may come on suddenly. The illness may be brief, or it may become chronic. Aplastic anemia can be very severe and even fatal.

Aplastic anemia develops when damage occurs to your bone marrow, slowing or shutting down the production of new blood cells. Bone marrow is a red, spongy material inside your bones that produces stem cells, which give rise to other cells. Stem cells in the bone marrow produce blood cells — red cells, white cells and platelets. In aplastic anemia, the bone marrow is described in medical terms as aplastic or hypoplastic — meaning that it's empty (aplastic) or contains very few blood cells (hypoplastic).

Factors that can temporarily or permanently injure bone marrow and affect blood cell production include:

Radiation and chemotherapy treatments. While these cancer-fighting therapies kill cancer cells, they can also damage healthy cells, including stem cells in bone marrow. Aplastic anemia can be a temporary side effect of these treatments.

Exposure to toxic chemicals. Exposure to toxic chemicals, such as some used in pesticides and insecticides, may cause aplastic anemia. Exposure to benzene — an ingredient in gasoline — also has been linked to aplastic anemia. This type of anemia may get better on its own if you avoid repeated exposure to the chemicals that caused your initial illness.

Use of certain drugs. Some medications, such as those used to treat rheumatoid arthritis and some antibiotics, can cause aplastic anemia.

A viral infection. Viral infections that affect bone marrow may play a role in the development of aplastic anemia in some people. Viruses that have been linked to the development of aplastic anemia include hepatitis, Epstein-Barr, cytomegalovirus, parvovirus B19 and HIV.

Pregnancy. Aplastic anemia that occurs in pregnancy may be related to an autoimmune problem — your immune system may attack your bone marrow during pregnancy.

Unknown factors. In many cases, doctors aren't able to identify the cause of aplastic anemia. This is called idiopathic aplastic anemia.

Confusion with myelodysplastic syndrome

Aplastic anemia can be mistaken for a condition called myelodysplastic syndrome. In this group of disorders, the bone marrow produces new blood cells, but they're deformed and underdeveloped. The bone marrow in myelodysplastic syndrome is sometimes called hyperplastic — meaning that it's packed with blood cells. But some people with myelodysplastic syndrome have empty marrow that's difficult to distinguish from aplastic anemia.

Connections with other rare disorders

Some people with aplastic anemia also have a rare disorder known as paroxysmal nocturnal hemoglobinuria. This disorder causes red blood cells to break down too soon. Paroxysmal nocturnal hemoglobinuria can lead to aplastic anemia, or aplastic anemia can evolve into paroxysmal nocturnal hemoglobinuria.

Fanconi's anemia is a rare, inherited disease that leads to aplastic anemia. Children born with it tend to be smaller than average and have birth defects, such as underdeveloped limbs. The disease is diagnosed with the help of blood tests.

Aplastic anemia is rare. Factors that may increase your risk include:

Treatment with high-dose radiation or chemotherapy for cancer

Exposure to toxic chemicals

The use of some prescription drugs — such as chloramphenicol, which is used to treat bacterial infections, and gold compounds used to treat rheumatoid arthritis

Certain blood diseases, autoimmune disorders and serious infections

Pregnancy, rarely

If you have signs or symptoms of aplastic anemia, start by making an appointment with your family doctor or a general practitioner. If your doctor suspects aplastic anemia, you'll likely be referred to a doctor who specializes in treating blood disorders (hematologist). If aplastic anemia comes on suddenly, you may begin treatment in the emergency room.

Here's some information to help you get ready for your appointment, and what to expect from your doctor.

What you can do

Write down any symptoms you're experiencing, including any that may seem unrelated to the reason for which you scheduled the appointment.

Write down key personal information, including any recent life changes, such as a new job, particularly one that exposes you to chemicals.

Make a list of all medications, as well as any vitamins or supplements, that you're taking.

Ask a family member or a friend to stay with you while you talk to your doctor. You may be tired or overwhelmed by all the information. A friend or a family member can take notes for you, or bring up questions you may forget to ask.

Write down questions you want to ask your doctor.

Preparing a list of questions ahead of time can help you make the most of your time together. For aplastic anemia, some basic questions to ask your doctor include:

What's the most likely cause of my symptoms?

Are there other possible causes for my symptoms?

What's my prognosis?

What treatments are available, and which do you recommend?

Are there any alternatives to the primary approach that you're suggesting?

I have another health condition. How can I best manage them together?

Are there any brochures or other printed material that I can take with me? What websites do you recommend?

In addition to the questions that you've prepared to ask your doctor, don't hesitate to ask questions during your appointment.

What to expect from your doctor

Your doctor is likely to ask you a number of questions, such as:

Have you had any infections?

Have you had any unexpected bleeding?

Have you felt more tired than usual?

When did you begin experiencing symptoms?

Is there anything new in your life, such as a new job or a new medication?

Does anything seem to improve your symptoms?

Does anything appear to worsen your symptoms?

To diagnose aplastic anemia, your doctor may recommend:

Blood tests. Normally, red blood cell, white blood cell and platelet levels stay within a certain range. Your doctor may suspect aplastic anemia when all three of these blood cell levels are very low.

Bone marrow biopsy. To confirm a diagnosis, you'll need to undergo a bone marrow biopsy. In this procedure, a doctor uses a needle to remove a small sample of bone marrow from a large bone in your body, such as your hipbone. The bone marrow sample is examined under a microscope to rule out other blood-related diseases. In aplastic anemia, bone marrow contains fewer blood cells than normal.

Once you've received a diagnosis of aplastic anemia, you may need additional tests to determine an underlying cause.

Treatments for aplastic anemia may include observation for mild cases, blood transfusions and medications for more-serious cases, and in severe cases, bone marrow transplantation. Severe aplastic anemia, in which your blood cell counts are extremely low, is life-threatening and requires immediate hospitalization for treatment.

Blood transfusions

Treatment for aplastic anemia usually involves blood transfusions to control bleeding and relieve anemia symptoms. Blood transfusions aren't a cure for aplastic anemia. But they do relieve signs and symptoms by providing blood cells that your bone marrow isn't producing. A transfusion may include:

While there's generally no limit to the number of blood cell transfusions you can have, complications can sometimes arise with multiple transfusions. Transfused red blood cells contain iron that can accumulate in your body and can damage vital organs if an iron overload isn't treated. Medications can help your body get rid of excess iron. Another possible complication is that over time, your body may develop antibodies to transfused blood cells, making them less effective at relieving symptoms. However, the use of immunosuppressant medication makes this complication less likely.

Stem cell transplant

A stem cell transplant to rebuild the bone marrow with stem cells from a donor may offer the only successful treatment option for people with severe aplastic anemia. A stem cell transplant, which is also called a bone marrow transplant, is generally the treatment of choice for people who are younger and have a matching donor — most often a sibling.

If a donor is found, your diseased bone marrow is first depleted with radiation or chemotherapy. Healthy stem cells from the donor are filtered from the blood. The healthy stem cells are injected intravenously into your bloodstream, where they migrate to the bone marrow cavities and begin generating new blood cells. The procedure requires a lengthy hospital stay. After the transplant, you'll receive drugs to help prevent rejection of the donated stem cells.

A stem cell transplant carries risks. There's a chance that your body may reject the transplant, leading to life-threatening complications. In addition, not everyone is a candidate for transplantation or can find a suitable donor.

Immunosuppressants

For people who can't undergo a bone marrow transplant or for those whose aplastic anemia may be due to an autoimmune disorder, treatment may involve drugs that alter or suppress the immune system (immunosuppressants).

Drugs such as cyclosporine (Gengraf, Neoral, Sandimmune) and anti-thymocyte globulin (Thymoglobulin) are examples. These drugs suppress the activity of immune cells that are damaging your bone marrow. This helps your bone marrow recover and generate new blood cells. Cyclosporine and anti-thymocyte globulin are often used in combination.

Corticosteroids, such as methylprednisolone (Medrol, Solu-Medrol), are often given at the same time as these drugs.

Immune-suppressing drugs can be very effective at treating aplastic anemia. The downside is that these drugs further weaken your immune system. It's also possible that after you stop taking these drugs, aplastic anemia may return.

Bone marrow stimulants

Certain drugs — including colony-stimulating factors, such as sargramostim (Leukine), filgrastim (Neupogen) and pegfilgrastim (Neulasta), and epoetin alfa (Epogen, Procrit) — may help stimulate the bone marrow to produce new blood cells. Growth factors are often used in combination with immune-suppressing drugs.

Antibiotics, antivirals

Having aplastic anemia weakens your immune system. You have fewer white blood cells in circulation to fight off germs. This leaves you susceptible to infections.

At the first sign of infection, such as a fever, see your doctor. You don't want the infection to get worse, because it could prove life-threatening. If you have severe aplastic anemia, your doctor may give you antibiotics or antiviral medications to help prevent infections.

Other treatments

Aplastic anemia caused by radiation and chemotherapy treatments for cancer usually improves once you complete those treatments. The same is true for most other drugs that induce aplastic anemia.

Pregnant women with aplastic anemia are treated with blood transfusions. For many women, pregnancy-related aplastic anemia improves once the pregnancy ends. If that doesn't happen, treatment is still necessary.

If you have aplastic anemia, take care of yourself by:

Resting when you need to. Anemia can cause fatigue and shortness of breath with even mild exertion. Take a break and rest when you need to.

Avoiding contact sports. Because of the risk of bleeding associated with a low platelet count, avoid activities that may result in a cut or fall.

Protecting yourself from germs. You can reduce your risk of infections with frequent hand-washing and by avoiding sick people. If you develop a fever or other indicators of an infection, see your doctor for treatment.

Tips to help you and your family better cope with your illness include:

Research your disease. The more you know, the better prepared you'll be to make treatment decisions.

Ask questions. Be sure to ask your doctor about anything related to your disease or treatment that you don't understand. It may help you to record or write down what your doctor tells you.

Be vocal. Don't be afraid to express any concerns you have to your doctor or any other health care professional treating you.

Seek support. Ask family and friends for emotional support. Ask them to consider becoming blood donors or bone marrow donors. Consider joining an aplastic anemia support group. It may be helpful to talk to others coping with the disease. Ask your doctor if he or she knows of any local support groups, or contact the Aplastic Anemia & MDS International Foundation. It offers a peer support network and can be reached at 800-747-2820.

Take care of yourself. Proper nutrition and sleep are important to optimize blood production.

There's generally no prevention for most cases of aplastic anemia. However, avoiding exposure to insecticides, herbicides, organic solvents, paint removers and other toxic chemicals may lower your risk of the disease.

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